1. Field of the Invention
The present invention relates to a sheet post-processing apparatus that performs post-processing such as stapling, punching, bookbinding and the like on sheets fed from an image formation apparatus such as a copy machine, printer and the like and the image formation apparatus installed with the sheet post-processing apparatus, and more particularly, to the sheet post-processing apparatus incorporated into an image formation apparatus and the image formation apparatus that effectively cools peripheral portions of the sheet post-processing apparatus.
2. Description of Related Art
With progress of multifunction of image formation apparatuses, such image formation apparatuses have been used that have sheet post-processing functions for performing post-processing on printed sheets. Examples of such a sheet post-processing functions are stapling, punching, bookbinding and the like. In many conventional image formation apparatuses, a sheet post-processing apparatus to perform such sheet post-processing is disposed outside the image formation apparatus.
Meanwhile, to reduce the size of the image formation apparatus with the sheet post-processing functions, apparatuses have been known which have the sheet post-processing functions and are disposed inside the image formation apparatus, instead of placing the sheet post-processing apparatus outside the image formation apparatus.
For example, JP 2003-335449 (Document 1) discloses an image formation apparatus where a sheet post-processing section is provided in U-shaped space formed by an original reading section, printing section and paper feed section.
Further, JP 2003-312920 (Document 2) also discloses an image formation apparatus that stores a sheet post-processing apparatus inside thereof, as in Document 1.
However, in a configuration where a sheet post-processing apparatus is disposed in the U-shaped space formed inside an image formation apparatus as in the image formation apparatus as described in Document 1, the sheet post-processing apparatus and image formation apparatus are disposed adjacent to each other, and heat tends to remain inside the apparatus in such a configuration. Particularly, when the sheet post-processing apparatus is disposed adjacent to the image formation apparatus, there is a possibility that heat generated on the image formation apparatus side, particularly, heat emitted from a fusing roller or the like, is conveyed to the sheet post-processing apparatus side, and therefore, some type of cooling structure is required also on the sheet post-processing apparatus side. Then, to obtain sufficient cooling effect by forming a cooling structure on the sheet post-processing apparatus side, it is necessary to guarantee sufficient air passages inside the apparatus, but it has been difficult to reserve sufficient air passages inside the conventional image formation apparatus.
Further, in the image formation apparatus as described in Document 2, sheets placed on a mount tray are cooled by sending cold air to the sheets on the tray from a fan apparatus provided above the tray.
However, in image formation apparatuses such as laser printers, temperatures ranging from about 150° C. to about 200° C. are applied to a sheet to fuse toner ink, and the ambient temperature of the sheet post-processing section thereby increases significantly. Therefore, even when cold air is sent to sheets placed on the mount tray, the sheets themselves become high temperatures inside a feeding path in the image formation apparatus, and thereby, are sometimes adhered to each other due to the viscosity of the toner ink, and the so-called blocking phenomenon (adhesion of ejected sheets) may occur. Further, when the temperature increases in an ejection path for a sheet to travel from the fusing section to an ejection outlet in the image formation apparatus, the sheet curls and becomes a cause of trouble such as a jam and the like.
The present invention is carried out in view of the above-mentioned problems in the conventional image formation apparatus, and it is an object of the invention to effectively cool with a simplified structure a sheet itself and/or a mechanical part of a post-processing apparatus and the like in the process of feeding the sheet from an image formation section to a mount tray.